Space News: Mega roundup!

[Brian G Turner]

It's been a while since I posted a Space News roundup!

A number of major stories have already been posted to the Science & Nature section of the forums, not least New Horizons Pictures of Ultima Thule, China lands on the dark side of the Moon, and Repeated radio bursts from Space.

However, here are a few more stories you may have missed over the past few weeks:


Asteroids

The image above is near-Earth asteroid SD220, which came close enough over December to be imaged with radar (see image above): Holiday asteroid imaged with NASA radar.

Meanwhile, data from NASA's Dawn probe shows that the asteroid Ceres has a surface covered with carbon-rich organic molecules: Team finds evidence for carbon-rich surface on Ceres


Planets

Researchers at Durham University say that computer simulations suggest a rocky planet bigger than Earth hit Uranaus, around 3-4 billion years ago, causing it's rotation to flip around 90 degrees: A big space crash likely made Uranus lopsided

Intriguing, they also say:

It's also possible that the big object that knocked over Uranus is still lurking in the solar system too far for us to see, said Green. It would explain some of the orbits of the planet and fit with a theory that a missing planet X is circling the sun well beyond Pluto, he said.

We know Venus has weather - now observations from the Japanese spacecraft Akatsuki seem to infer jet streams driving the cloud formations: Giant pattern discovered in the clouds of planet Venus

Mars has also been in the news, with ice imaged at its north pole (see pic above): Pictures reveal 'winter wonderland' on Mars. Curiously, though, scientists are struggling to detect methane at the surface, which some speculate means it might follow a biological cycle in line with the seasons: Remember the discovery of methane in the martian atmosphere? Now scientists can't find any evidence of it, at all

Speaking of seasons, Saturn apparently turns a hazy shade of blue in winter: Rings make Saturn shadier, bluer and less hazy in winter. Less pleasantly, Saturn's rings seem to be disappearing at a faster rate than initially thought, with them expected to now disappear within 300 million years: NASA research reveals Saturn is losing its rings at 'worst-case-scenario' rate. More mysteriously, analysis of water ice in Saturn's system shows it's isotope ratios are very similar to that on Earth - with the exception of the moon Phoebe, which has already been suggested was a captured asteroid: The water in Saturn's rings and satellites is like that on Earth except for moon Phoebe, which is out of this world


Exoplanets

One of the more exciting stories over December was the detection not just of a possible rogue planet between the stars, but of aurora activity detected upon one: An aurora glows over a (possible) rogue planet

Brown dwarfs are one of the more enigmatic bodies in the universe - too big to be a planet, too small to be a star. And they keep turning up in unexpected places, not least HATS-70b, which has been the first detected around a tiny A-class star: Astronomers detect low-mass brown dwarf around A-type main-sequence star

Exoplanets continue to surprise us with their variety - the latest of which is a planet whose mass doesn't fit neatly into current models of planet formation: Nature's magnifying glass reveals unexpected intermediate mass exoplanets

Additionally, we keep seeing more exotic features:

• A helium planet that inflates: Helium exoplanet inflated like a balloon, research shows
• An exoplanet with tail like a comet: An exoplanet loses its atmosphere in the form of a tail
• An exoplanet with rubies in the sky, like diamonds - and sapphires: Sapphires and rubies in the sky

In fact, more planets forming around young stars than expected: Unknown treasure trove of planets found hiding in dust.

It's not all good news, though. We now know that red dwarf stars - the most numerous in our galaxy - may be one of the most common places to find planets. Unfortunately, current simulations suggest we're unlikely to find conditions favourable to life as we know it: Young planets orbiting red dwarfs may lack ingredients for life.

Even still, planetary formation seems to be happening at a faster rate than expected: The epoch of planet formation, times twenty

Meanwhile, some odd orbital angles may be due to kinks in the prot-planetary disk: Early protostar already has a warped disk


Galaxies

It's not just proto-planetary disks that can be warped - apparently, our own galaxy shows strange corrugated features: The corrugated galaxy: Milky Way may be much larger than previously estimated

Continued observations have also led to the discovery of a new dwarf galaxy orbiting the Milky Way: Enormous dwarf satellite galaxy of Milky Way discovered as well as Three new open clusters discovered in the Milky Way. In fact, Nearly a third of all galaxy clusters may have been previously unnoticed.

While everything is looking busier around many galaxies, not least with A cluster of clusters: The globulars of Coma, some galaxies are surprisingly lonely: The lonely giant: Milky Way-sized galaxy lacking galactic neighbors

Everything remains hectic in our galaxy, with the striking news - literally so - that the Large Magellenic Cloud might be due to collide with us in 2 billion years, before the arrival of Andromeda: Catastrophic galactic collision could send Solar System flying into space


Stars

A few especially interesting stories about stars, not least that Astronomers discover first direct evidence of white dwarf stars solidifying into crystals

Meanwhile, modelling appears to account for the development of two-thirds of observed binary stars: How do stellar binaries form?. Which begs the question of what process was behind the other third?


Miscellaneous

• Normally we'd expect a Black Hole to rip apart any close observer - new calculations claim otherwise: Rotating black holes may serve as gentle portals for hyperspace travel
• Something like 'Oumaumau comes every 30 years? Interstellar objects like 'Oumuamua probably crash into the sun every 30 years
• Why we kill probes in deep space: Probe killers in deep space
• Pansperima - more on life from asteroids: Lab study adds credence to life arriving on Earth from asteroids theory
• Most distant object in the solar system discovered: Meet your very, *very* distant solar system neighbor 2018 VG18

 

[Al Jackson]

There were more gravitational wave detections in 2018.

Four new gravitational wave detections announced, including the most

 

[Robert Zwilling]

So many new ideas about old things. Saturn's water matches ours which probably means our idea of where the inner/outer boundary of the solar system is farther out than was thought. Maybe there is a lot of stuff in what was thought to be empty space past Pluto. Like an enormous flock of dwarf planets, at least one large planet, and an Earth sized planet if it didn't blow up when it hit Uranus, tilting it over. Maybe glancing blows are more common than realized, something big comes in and instead of total destruction it glances off instead of plowing headlong into the object.

Dwarf stars have solid crystalized cores, maybe that's where dilithium crystals come from. The Earth's core contains possibly a small crystalized solid center, perhaps when the Earth cools down, it will have a huge crystal inside of it, coated with a rock crust that gets blown off when the Sun blows up, it might survive and wander through space.

Now the Milky Way isn't flat, just like the Earth isn't flat, with so little around us maybe we are in a empty zone between two peaks.

Went looking for a map of dead stars only which was a total bust, for real stars anyway, but found an interesting equirectangular projection of the night sky in galactic coordinates of Pulsars, Gamma Ray Bursts, Super Novas. It shows the entire sky as visible from Earth with the Milky Way Galaxy running through the middle of the screen. I don't get the alignment, I could use a you are there arrow. It's a time based display (move cursor to move through time) of the discoveries of Super Novas, Gamma Ray Bursts, and Pulsars, starting in 1895. The pulsars range from 0 to 250,000 light years away. Gamma ray data starts in 1977.
Visual history of Gamma Ray Bursts, Super Novas, and Pulsars

 

[Bick]

Fascinating stuff, thanks for posting.

 

[J Riff]

Gravitational waves making a comeback, about time.

 

[Brian G Turner]

t's not all good news, though. We now know that red dwarf stars - the most numerous in our galaxy - may be one of the most common places to find planets. Unfortunately, current simulations suggest we're unlikely to find conditions favourable to life as we know it: Young planets orbiting red dwarfs may lack ingredients for life.

Just to come back to this - Phil Plait explains this in more detail here Rocky worlds around red dwarfs may get blasted clean of water and makes the following comment:

Once these planets cool down after formation, they may very well be deserts.

That's a bummer.

However, isn't that exactly what is theorized happened to Earth - hence "water from icy comets"?

 

[Venusian Broon]

Just to come back to this - Phil Plait explains this in more detail here Rocky worlds around red dwarfs may get blasted clean of water and makes the following comment:



However, isn't that exactly what is theorized happened to Earth - hence "water from icy comets"?

I haven't read the article but reading your comment @Brian G Turner made me think of two things

1) Being a red dwarf, the mass of material in the disc that formed the system is likely to be significantly less than the amount of mass in our system - hence less icy bodies to transfer water to any planet after formation

2) A scenario of the NICE model about the formation of our solar system suggests that the movement of Jupiter out, caused Neptune, at the time orbiting inside Uranus' orbit, to careen widely into the then much closer Oort cloud, causing huge numbers of icy comets to widely disperse and help cause the late heavy bombardment - where we suspect that Earth received quite a lot of it's water (and interesting organic material)

Not all system will have identical planetary constituents, nor are you guaranteed that a Jovian world will oblige you and do what the above model suggest! See for example the numerous Hot Jupiter systems.

 

[Robert Zwilling]

There was an article a while back that said the there was a lot more water locked up in the crust of the Earth and it goes far below the surface, than the water on the surface. The water locked up in different minerals far below the surface is proof that it exists but doesn't say how it got there. It seems unlikely the water locked in the crust got there by comets striking the Earth building up oceans of water that then gets folded into the crust by the cycling of tectonic plates as they travel from the surface to deep inside the crust. The comets are definitely adding new water to the system.

One question could be is it possible that the cycling of the plates from under the crust back to the surface bring up water from within the crust. Over a period of time that could release water to the surface. In its early stages the plate movements could have been cycling a lot faster than they are now. The atmosphere could have been thinner making it much colder and condensing any water that came up from the depths.

Perhaps water planets are born with water which has to be squeezed out. If it wasn't locked up so tight it wouldn't make it past the solidification process. So long as the core is molten and the plates are still moving, the fact that there is still far more water under the crust might make it possible for it to come back out again. Perhaps planets that get all their water from comets would have to be in the crossroads of comet paths, getting struck endlessly. I? think that would be rare.

Another question would be how many of the planets have minerals that have water in them. I don't think we are anywhere near close to be able to determine the geology of the planets we are discovering. Water filled planets could be rare, the norm, or random. The mineral content could be one factor that determines if a planet will be capable of supporting life. The tectonic flow of rocks folding and unfolding releasing and absorbing substances could be more like the polished flows of origami than just brute conveyor belt random crushing and melting and recycling whatever is available.

Then there is the question of how many different life forms are that are not based on water. What would that kind of mineral base look like. Folding molecules could possibly mechanically create living systems that no need for water, only the ability to harness energy so it can continue to recreate itself.